Reversing drum switch



Dec. 25, 1956 .1. J. GRIBBLE 2,775,661

REVERSING DRUM SWITCH Filed July 15, 1955 IM 'ENTOR.

Z- E Jase 1- Jan-1x76.

nited States Patent REVERSING DRUM SWITCH Joseph J. Gribble, Shorewood, Wis., assignor to Square D Company, Detroit, Mich, a corporation of Michigan Application July 15, 1953, Serial No. 368,090

7 Claims. (Cl.200--1) This invention relates to a reversing drum switch having enclosed cooperating stationary and movable contacts, the latter being mounted on a drum operated by an operating handle at the exterior of the enclosure into forward and reverse positions.

An object of this invention is a reversing drum switch providing for either indexed or momentary forward and reverse positions as desired and in which the change-over from index to momentary and from momentary to index may be readily effected at the exterior of the enclosure without the use of special tools.

Another object of the invention is a reversing drum switch in which there are provided two indexed off positions 180 apart and indexed forward and reverse positions at either side of one only of said 0 positions and non-indexed forward and reverse positions on either side of the other off position and in which an operating handle may be readily assembled with the drum in either of the 180 reversed positions, stationary contacts and the movable contacts on the drum being arranged in 180 relationship to provide for forward and reverse contact arrangement for the same position of the handle with the drum in either of the 180 reversed positions relative to the handle.

Other objects and features of the invention will be readily apparent to those skilled in the art from the spec ification and appended drawing illustrating certain preferred embodiments in which:

Figure 1 is a front elevational view of the reverse drum switch according to the present invention with a portion of the enclosure broken away to show internal parts.

Figure 2 is a sectional view on the line 11-11 of Figure 1.

Figure 3 is a partial sectional view on the line IIIIII of Figure 1.

Figure 4 is a detail view on the line IV-IV of Figure 2.

Figure 5 is a view similar to Figure 2 but showing the drum rotated through 180 relative to the handle from the position shown in Figure 2.

The reversing drum switch specifically illustrated in the drawing as a representation of the invention is shown as comprising a generally U-shaped supporting and enclosing member 1 having mounted within the bight thereof an insulating member 2 with a large thin insulating sheet 3 disposed therebetween and across the inner face of the member. In the upper face of the insulating block 2 and in the upper end 4 of the member 1 is pivoted a pin 5 upon which is pivotally mounted a lever 6 biased in a counterclockwise direction by a tension spring 7 and carrying at its free end an indexing roller 8.

In the lower leg (not shown) of the member 1 is pivotally mounted one end of a drum 9 having a plurality of movable contacts 11 mounted thereon between insulating discs 12. The upper end of the drum 9 is pivoted by a shaft 13 within an opening through a top plate 14 rigidly secured to the top leg 4 of the member 1 as by means of studs 15. The shaft 13 is preferably rectan- 'ice gular in shape, as shown in Figures 2 and 5, and has slidably mounted on its outer end a hub 16 into which is threaded an operating handle 17 carrying a knob 18. The inner end of the handle 17 is provided with a reduced portion 19 received within a transverse opening 21 in the end of the shaft 13, thus serving to engage the handle 17, hub 16 and shaft 13 together for rotation as a unit while providing for ready disassembly of the parts by the removal of the handle 17 by screwing it out of the hub 16 after which the hub may be readily slidably removed from the shaft 13.

Mounted at opposite sides of the insulating block 2 are a plurality of pairs of stationary contact arms 22 and 23 carrying contact tips 24 disposed diametrically opposite each other at opposite sides of the drum. The movable contacts 11 are arranged with contact surfaces disposed apart so that they will cooperate with the contact tips 24 with the drum in either of two positions 180 apart. Keyed ,on the shaft 13 and maintained thereon by a locking ring 26 is an indexing plate 27 having a first indexing notch 28 and a second indexing notch 29 determining two off positions for the drum 9, disposed as shown in Figures 2 and 5, 180 apart. These notches cooperate with the roller 8 on the end of the biased lever 6 to index the drum in the two off positions spaced apart 180". On opposite sides of the notch 29 are notches 31 and 32 which cooperate with the roller 3 to index the drum 9 in the forward and reverse positions respectively, thus providing for maintained contact engagement in the operating position of the switch. A front U-shaped enclosing member 10 cooperates with the U-shaped member 1 to complete the enclosure for the switch.

In the switch position shown in Figures 1, 2 and 3, the handle 17 and drum 9 are shown in the off position and are assembled to provide for indexed forward and reverse positions. In this off position, the roller 8 is indexed with the notch 29 to provide a stable position for the parts with the contacts disengaged. To move the switch in the forward operating position, the handle 17 is rotated in a clockwise direction until the roller 8 engages within the notch 31 in the plate 27 to index the drum in the forward position with the proper movable contacts engaged with the stationary tips 24. This forms a stable operating position in which the parts will remain until manually moved therefrom. Similarly, in the reverse position the handle and drum are rotated counterclockwise until the roller 8 indexes in the notch 32 and the parts are held in the position corresponding to a reverse rotation of a motor with which the switch may be associated. The extremes of rotation of the handle and drum are determined by the engagement of the end walls of an opening in the undersurface of the hub 16, with the heads of the stationary studs 15.

To provide for momentary forward and reverse positions, the handle 17 is removed from the hub 16 and the hub slidably removed from the shaft 13. Thereafter, the reduced end portion 19 of the handle 17 is again inserted into opening 21 of the shaft 13 Without the hub and the shaft 13 and the drum 9 are rotated through 180, if the parts were originally in the off position or through a lesser or greater angle if the parts were in the indexed forward or reverse positions. In either event, the drum 9 and shaft 13 now assume a position with the roller 8 indexed in the notch 28 in the plate 27. The hub 13 is re-engaged with the shaft 13 in the position now 180 reversed from that which it previously had on the shaft and the handle 17 again threaded into the hub with the reduced end 19 in the opening 21 to hold the parts together as a unit. The switch is then in the position shown in Figure 5 and rotation of the handle 17 in counterclockwise and clockwise directions again places the appropriate contact 11 into engagement with the stationary contact tips 24 for forward and reverse positions respectively. Thus, it will be seen that the handle operation is identical for forward and reverse positions whether the parts are assembled as in Figure 2 or in Figure 5. However, in the arrangement of Figure 5, it is seen that there is no indexing of the roller 8 and plate 27 in the forward and reverse positions of the drum so that these positions become momentary in the sense that they must be maintained or the parts will automatically return to the position under the bias of the spring 7 exerted through lever 6 and roller 8 upon the flat edge of the plate 27.

It Will be seen that this change-over of the switch from index to momentary operation is effected entirely from the exterior of the enclosure and without extra tools, the reduced end of the handle 17 facilitating the rotation of the shaft 13, not being essential therefor. The change back to indexed relation is effected in the same manner as was the change to momentary operation and again is carried out from the exterior of the enclosure.

While certain preferred embodiments of the invention have been specifically disclosed, it is understood that the invention is not limited thereto, as many variations will be readily apparent to those skilled in the art and the invention is to be given its broadest possible interpretation within the terms of the following claims.

What is claimed is:

1. In a reversing drum switch, a plurality of pairs of stationary contacts, a switching drum disposed between said stationary contacts and carrying movable contacts cooperating therewith, said stationary contacts being spaced substantially 180 apart about the drum and said movable contacts being arranged in pairs with the contacts in each pair spaced substantially 180, an indexing plate mounted to be rotatable with said drum, indexing otf" notches on said plate 180 apart and indexing forward and reverse notches on opposite sides of one only of said off notches, spring loaded means engaging said notches to index plate and drum positions, an operating handle for said drum and means reversing the drum and handle engagement by substantially 180 to provide for momentary or indexed forward and reverse positions of the drum for the same positions of the handle.

2. in a reversing drum switch, a plurality of pairs of stationary contacts, a switching drum disposed between said stationary contacts and carrying movable contacts cooperating therewith, said stationary contacts being spac d substantially 180 apart about the drum and said movable contacts being arranged in pairs with the contacts in each pair spaced substantially 180, an indexing plate mounted to be rotatable with said drum, indexing oft notches on said plate 180 apart and indexing for ward and reverse notches on opposite sides of one only of said otf notches, spring loaded means engaging said notches to index plate and drum positions, an operating handle for said drum, means reversing the drum and handle engagement by substantially 180 to provide for momentary or indexed forward and reverse positions of the drum for the same positions of the handle, said reversal of engagement between the handle and drum being readily effected by removing the handle in one oi'F position, rotating the drum through substantially 180, and reassembling the handle in its initial space position now reversed substantially 180 relative to the drum.

3. in a reversing drum switch, a plurality of pairs of stationary contacts, a switching drum disposed between said stationary contacts and carrying movable contacts cooperating therewith, said stationary contacts being spaced substantially 180 apart about the drum and said movable contacts being arranged in pairs with the con tacts in each pair spaced substantially 180, an indexing plate mounted to be rotatable with said drum, indexing "01P notches on said plate 180 apart and indexing forward and reverse notches on opposite sides of one only of said off notches, spring loaded means engaging said notches to index plate and drum positions, an operating handle for said drum, means reversing the drum and handle engagement by substantially to provide for momentary or indexed forward and reverse positions of the drum for the same positions of the handle, an enclosure for said drum and the cooperating movable and stationary contacts, said reversal of engagement of said handle and drum being readily effected by disengagement of the handle and rotation of the drum through 180 relative to the handle with reassembly of the handle and drum thereafter, said disengagement, rotation and reassembly being readily effected entirely from the exterior of the switch enclosure.

4. In a reversing drum switch, a plurality of pairs of stationary contacts, a. switching drum disposed between said stationary contacts and carrying movable contacts cooperating therewith, said stationary contacts being spaced substantially 180 apart about the drum and said movable contacts being arranged in pairs with the contacts in each pair spaced substantially 180, an indexing plate mounted to be rotatable with said drum, indexing otf notches on said plate 180 apart and indexing forward and reverse notches on opposite sides of one only of said off notches, spring loaded means engaging said notches to index plate and drum positions, an enclosure for the switch, a rotatable supporting shaft extending through the enclosure and carrying said drum therewithin, a hub assembly mounted on said shaft at the exterior of the enclosure, and an operating handle carried by said hub, the hub being readily assembled with the shaft in two positions relative thereto spaced substantially 180 apart to provide for momentary or indexed forward and reverse positions of the drum for the same positions of the handle.

5. In a reversing drum switch, a plurality of pairs of stationary contacts, a switching drum disposed between said stationary contacts and carrying movable contacts cooperating therewith, said stationary contacts being spaced substantially 180 apart about the drum and said movable contacts being arranged in pairs with the contacts in each pair spaced substantially 180, an indexing plate mounted to be rotatable with said drum, indexing off notches on said plate 180 apart and indexing forward and reverse notches on opposite sides of one only of said off notches, spring loaded means engaging said notches to index plate and drum positions, a rotatable supporting shaft extending through the enclosure and carrying said drum, a hub assembly mounted on said shaft at the exterior of the enclosure, and an operating handle threaded through said hub and into engagement with the shaft to lock the handle, hub and shaft together for rotation as a unit, said hub being mountable on said shaft in either of two positions spaced substantially 180 apart to provide for momentary or indexed forward and reverse positions of the drum for the same positions of the handle.

6. in a reversing drum switch, a plurality of pairs of stationary contacts, a switching drum disposed between said stationary contacts and carrying movable contacts cooperating therewith, said stationary contacts being spaced substantially 180 apart about the drum and said movable contacts being arranged in pairs with the contacts in each pair spaced substantially 180, an indexing plate mounted to be rotatable with said drum, indexing off notches on said plate 180 apart and indexing forward and reverse notches on opposite sides of one only of said off notches, spring loaded means engaging said notches to index plate and drum positions, an enclosure for the switch, a rotatable supporting shaft extending through the enclosure and carrying said drum therewithin, a hub removably mounted on said shaft at the exterior of the enclosure, an operating handle threaded in said hub, an opening through said shaft with the end of said handle projecting within said opening to lock the handle, hub and shaft together as a unit, said hub and 5 handle being mountable on the shaft in either of two positions spaced substantially 180 apart to provide for momentary or indexed forward and reverse positions of the drum for the same positions of the handle.

7. In a reversing drum switch, a plurality of pairs of stationary contacts, a switching drum disposed between said stationary contacts and carrying movable contacts cooperating therewith, said stationary contacts being spaced substantially 180 apart about the drum and said movable contacts being arranged in pairs with the contacts in each pair spaced substantially 180, an indexing plate mounted to be rotatable with said drum, indexing o notches on said plate 180 apart and indexing forward and reverse notches on opposite sides of one only of said oif notches, spring loaded means engaging said notches to index plate and drum positions, an enclosure for the switch, a rotatable supporting shaft extending through the enclosure and carrying said drum therewithin, a hub removably mounted on said shaft at the exterior of the enclosure, an operating handle threaded in said shaft, an opening through said shaft and a reduced end on said handle pr'm jecting within said opening to lock the handle, hub and shaft together as a unit, said hub and handle being mountable on the shaft in either of two positions spaced substantially 180 apart to provide for momentary or indexed forward and reverse positions of the drum for the same positions of the handle, said reduced end being insertable in said shaft opening when the hub is removed and serving as a tool for rotating the shaft and drum.

References Cited in the file of this patent UNITED STATES PATENTS 1,389,142 James Aug. 30, 1921 2,107,045 Rasmussen Feb. 1, 1938 2,289,643 Furnas et a1 July 14, 1942 FOREIGN PATENTS 56,702 Holland July 15, 1944 

